Problem: $ { \left[\begin{array}{rr}{0} & {0} \\ {4} & {-1} \\ {0} & {4}\end{array}\right]-\left[\begin{array}{rr}{1} & {1} \\ {4} & {-2} \\ {3} & {0}\end{array}\right] = {?} } $
To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rr}{0}-{1} & {0}-{1} \\ {4}-{4} & {-1}-{-2} \\ {0}-{3} & {4}-{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{-1} & {-1} \\ {0} & {1} \\ {-3} & {4}\end{array}\right]}$